c# - How to save a file in a list box into a .txt file? -

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• how permanently save input given user in c# console application? 2 answers

how save file in list box .txt file?

return string.format("{0} = {1}",    jaialainumber, "₱" + bet.tostring()); how save file on .txt file? 

here's code of program. ): ^_^ .

public partial class frmjaialai : form {     list<jaialai> source;      public frmjaialai()     {         initializecomponent();     }              private void frmjaialai_load(object sender, eventargs e)     {         source = new list<jaialai>();               }      private void btnadd_click(object sender, eventargs e)     {         int bet;         if (string.isnullorempty(txtjaialainumber.text) || !int32.tryparse(txtbet.text, out bet))         {             messagebox.show("must required field.", "entry error");             return;         }         var existingproduct = source.where(x => x.jaialainumber == txtjaialainumber.text).singleordefault();         if (existingproduct != null)         {             existingproduct.bet += bet;         }         else             source.add(new jaialai { bet = bet, jaialainumber = txtjaialainumber.text });          lstjaialainumberslist.datasource = null;         lstjaialainumberslist.datasource = source;          txtjaialainumber.text = "";           }      public class jaialai     {         public string jaialainumber { get; set; }         public int bet { get; set; }          public override string tostring()         {             return string.format("{0} = {1}",                  jaialainumber, "₱" + bet.tostring());         }     } 

if understood correct, want write list<jaialai> file. in case can use file.writealllines.

file.writealllines("file-path", source.select(x => x.tostring())); 

the first parameter path of file. second parameter ienumerable<string> contains lines.
select method calls tostring method items strings can written file. can change lambda write other stuff per record file.